Twin tank rock duster



March 1, 1966 G. D. GURNEY TWIN TANK ROCK DUSTER 5 SheetsSheet 1 Filed March 5, 1964 I N VENTOR. Glam D. Gurney ATTORNEYS March 1, 1966 G. D. GURNEY 3,237,993

TWIN TANK ROCK DUSTER Filed March 5, 1964 3 Sheets-Sheet 2 INVENTOR.

Glenn D. Gurney BY 7 WW4? 44M ATTORNEYS March 1, 1966 G. D. GURNEY TWIN TANK ROCK DUSTER 3 Sheets-Sheet 5 Filed March 5, 1964 QvIL INVENTOR Glenn D. Gurney SMWs M4 ATTORNEYS United States Patent 3,237,993 TWIN TANK ROCK DUSTER Glenn D. Gurney, Canton, Ohio, assignor to The American Mine Door Company, Canton, Ohio, 21 corporation of Ohio Filed Mar. 5, 1964, Ser. No. 349,601 Claims. (Cl. 302-53) The invention relates to apparatus for spraying rock dust in the corridors, rooms and elsewhere in coal mine cavities.

It is required by law that coal dust on the walls, ceilings and rooms of such mine cavities be covered by, or mixed with, a prescribed proportion of non-combustible material, such as pulverulent limestone or the like, to prevent, or at least lessen the danger of explosion of the coal dust.

Such apparatus as has been commonly used for this purpose is usually carried upon a vehicle or sled arranged to be driven, pushed or dragged through the mine cavities, and provided with a nozzle or a comparatively short hose through which the rock dust is discharged from the apparatus onto the ceilings, walls and floors of the mine cavities. This has required that the entire apparatus must be conveyed throughout substantially the entire length of each mine room, corridor or other cavity to be dusted.

Also, such apparatus as is now in use is provided with a single hopper or the like for the rock dust, and when the supply of dust is exhausted the apparatus must be removed to a remote point for replenishing the supply of dust.

A primary object of the present invention is to provide a rock duster having twin tanks for containing the rock dust, with means for discharging the dust, under air pressure, from one tank at a time.

Another object of the invention is to provide means for filling one tank with rock dust, while the dust is being discharged from the other tank under air pressure.

A further object of the invention is to provide an outlet junction having a single hose connection communicating with the discharge outlets of both tanks.

A still further object of the invention is to provide a flipper valve in the outlet junction which operates automatically to close the discharge outlet of the tank being filled, by air pressure from the tank which is discharging.

Another object of the invention is to provide a rock duster apparatus which is capable of using a discharge hose several hundred feet long for spraying dust upon the walls, ceilings and floors of mine cavities, thus making it unnecessary to convey the apparatus throughout the entire length of every corridor, room or the like being dusted.

A further object of the invention is to provide a twin tank rock duster of the character referred to in which a vibrator is provided upon the conical lower end of each tank, the vibrator being operated by compressed air, a four-way valve being provided for admitting compressed air to the vibrator upon the tank which is discharging and to said tank, and at the same time exhausting air from the tank which is being filled.

A still further object of the invention is to provide a clean-out jet with air hose connection for cleaning the bearing of the flipper valve.

The above and other objects, apparent from the drawings and following description, may be attained, the above described difliculties overcome and the advantages and results obtained, by the apparatus, construction, arrangements and combinations, subcombinations and parts which comprise the present invention, a preferred embodiment of which, illustrative of the best mode in which applicant has comtemplated applying the principle, being set forth "ice in detail in the following description and illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevation of a twin tank duster embodiing the invention, parts being broken away for the purpose of illustration;

FIG. 2 is a top plan view of the apparatus shown in FIG. 1;

FIG. 3 is an end view of the apparatus looking from the left, as viewed in FIGS. 1 and 2, with parts broken away for the purpose of illustration;

FIG. 4 is a section on the line 44, FIG. 3, showing the connection of the discharge outlets of the two tanks to the outlet junction to which the discharge hose is connected;

FIG. 5 is an enlarged fragmentary plan sectional view of the outlet junction;

FIG. 6 is a section through the outlet junction, taken on the line 6-6, FIG. 5, showing the clean-out jet connection for the bearing of the flipper valve; and

FIG. 7 is a vertical section, as on the line 7-7, FIG. 2, showing the air inlet, air filter, shut-oif air valve, safety valve and hose to the clean-out jet connection.

The two tanks are indicated generally at 11, bein supported in spaced relation by the upright frame members 2 upon the horizontal frame members 3 which may be in the form of runners. Each of the horizontal frame members 3 has the horizontal flange 4 and vertical flange 5 and has the opposite ends upwardly inclined as at 6 to facilitate moving the same over the ground.

Each of the tanks 1 may be cylindrical, as shown, and is provided with the depending cone 7 having the central filling opening 3 surrounded by an O-ring 9 within the circular frame 10. A closure cone 11 has ears 12 at its upper end, pivotally connected at 13 to one end of the link 14, the other end of which is pivoted at 15 to the ears 16 extending upwardly from the depending cone 7.

The closure handle 17 is also pivoted upon the bolt 15 and has the lug 18 at its inner end extending beneath the link 14 so that when the handle 17 is moved outward and downward to the position shown in FIG. 3 the lug 18 thereon engaging under the edge of the link 14 will swing the same upward pulling the closure cone 11 tightly against the O-ring 9.

The lower portion of each tank 1 is of conical shape, as shown at 19, terminating at its lower end in the discharge opening 20 to which a base fitting 21 is attached. Each of the base fittings has a flange 22 at its upper end with peripheral openings or slots 23 therein. Hooks 24 are located through these slots, the upper hooked ends thereof engaging in the loops 25 welded upon the exterior of the conical lower end 19 of the tank.

The lower ends of the hooks 24 are screw-threaded, as indicated at 26, and hand nuts 27 are provided thereon for drawing the upper end of each base fitting 21 tightly against the discharge end of the corresponding tank.

A hose connection 28 is provided upon the other end of each base fitting 21 and a flexible hose 29 is connected to each hose connection 28, the other end of each hose 29 being connected to hose connections 30 upon the outlet junction indicated generally at 31.

As best shown in FIG. 5, the outlet junction 31 may be formed of two castings, or the like, indicated at 32 and 33, provided with mating flanges 34, through which they are connected together as by the screws 35.

Two similar diverging outlet necks 36 are formed in the casting 32, and receive the outlet liners 37, having their inner ends extended into the outlet junction. The outer ends of these liners are of reduced thickness and the hose couplings 30 are formed thereon.

The member 33 of the outlet junction tapers from the flange 34 as indicated at 38 toward the discharge end,

which is provided with a hose coupling 39 to which the discharge hose 40 is connected. This hose may be several hundred feet in length, and may be provided with a nozzle of suitable design at its discharge end.

Bosses 41 may be formed upon the interior of the member 32, between the outlet necks 36, to receive the pivot stem 42 of a flipper valve indicated generally at 43. This flipper valve is adapted to be operated by compressed air from the tank which is discharging dust, to hold the outlet from the other tank closed while said other tank is being filled with dust.

The flipper valve 43 is formed of rubber or similar material, opposite sides thereof being conical, as indicated at 44, to seat upon the valve seats 45 and the inner ends of the outlet liners 37.

A bearing member 46 has a shank portion 47 embedded in or integral with the rubber flipper valve 43. A bushing 48 is interposed between the flipper valve bearing member 46 and the pivot stem 42.

For the purpose of keeping the bearing of the flipper valve 43 clean at all times a clean-out jet is provided and connected to a source of compressed air, so that continuous jets of air under pressure are directed against the flipper valve bearing.

As shown in FIGS. 5 and 6, a bore 49, parallel with the flipper valve pivot stem 42, is provided in the center of the wall 50 of the member 32 of the outlet junction, the inner end of said bore being closed, as at 51 in FIG. 6, and the outer open end of the bore being threaded as at 52.

Small apertures or jet passages 53 extend inwardly from the bore 49, through the inner surface of the wall 50, and are directed toward the bearing member 46 of the flipper valve. A coupling 54, on one end of an air hose 55, is attached to the threaded end 52 of the bore 49. The other end of the hose 55 is connected to a source of air under pressure as will be later described.

Compressed air from a compressor, or other suitable source of air under pressure, may be supplied through a hose 56 (FIG. 7) to the inlet 57 of an air filter 58. The air filter may be supported by a strap 59 connected to the frame member 60 attached at opposite ends to the tanks 1-1, as by welding or the like.

An air cock 61 is shown connected to the lower side of the air filter 58. The outlet pipe 62 is also connected to the lower side of the air filter, and is provided with a shut-off valve 63 adapted to be operated by a hand wheel 64.

Beyond the shut-off valve 63, the pipe 62 is connected to a T-connection 65. A hose coupling 66 is provided on one end of the T-connection 65, and the hose 55, leading to the clean-out jet connection 52, is attached thereto.

Thus, at all times, except when the shut-off valve 63 may be closed, at which time of course the apparatus will not be operating, there will be a continuous supply of air under pressure to the clean-out jet connection for the flipper valve bearing.

The other end of the T-connection is connected to one side of a four-way connection 67, to which are also connected a safety valve 68 and a pressure gauge 69. A pipe 70 connects the four-way connection 67 to the four-way valve 71, adapted to be operated by the handle 72.

The four-way valve 71 is mounted upon a frame member 73 welded or otherwise connected at opposite ends to the tanks 11, or otherwise suitably supported upon a stationary portion of the apparatus.

Pipes 74 and 75 are connected to opposite sides 76 and 77, respectively, of the four-way valve. The air inlet pipe 70 is connected to the top 78, and the lower side 79 of the four-way valve is open to the atmosphere.

The pipe 74 is connected to a T-connection 80, the upper end of which is connected by pipe 81 to the upper portion of one of the tanks 1, as indicated at 82. A

pipe 83 leads from the lower end of the T-connection 80 to a compressed air-operated vibrator 84, which is connected, as at 85, to the conical lower end 19 of the same tank to which the pipe 81 is connected.

The pipe 75, from the other side of the four-way valve 71, is connected to a T-connection 80a, the upper end of which is connected, by pipe 81a, to the upper portion of the other tank 1, as indicated at 82a. A pipe 83a leads from the lower end of the T-connection 80a to a compressed air-operated vibrator 84a, which is connected, as at 85a, to the conical lower end 19 of said other tank.

In the operation of the apparatus to spray rock dust upon the ceiling, walls and floor of a corridor, room, or other mine cavity, the twin tank duster, as illustrated and above described, is moved to a location such that the hose 40 will reach the area to be dusted.

The shut-off valve 63 is opened and air under pressure is admitted from a compressor, or other suitable source of supply, through the inlet hose 56 to the air filter 58, and thence through the pipe 62, valve 63, T- connection 65, four-way connection 67 and pipe 70 to the four-way valve 71.

Some of the air from the four-way connection 67 will pass down through the hose 55 to the clean-out jet connection 49, for blowing jets of air through the jet passages 53 onto the bearing 46 of the flipper valve 43, to remove dust therefrom and keep the same clean at all tunes.

The pressure gauge 69 will at all times register the air pressure in the system. The safety valve 68 may be operated to relieve the air pressure at any time that the pressure approaches the danger point.

Each tank 1 may be filled to the desired height with rock dust, by raising the closure handle 17 to lower the closure cone 11 away from the open bottom of the depending cone 7, and then charging the desired amount of rock dust through the charging opening 8 into the tank.

When it is desired to discharge the dust from either tank, the handle 17 must be depressed raising the cone 11 against the O ring 9, as the four-way valve is operated, and held sufficiently long to permit pressure in the tank to maintain the cone 11 against the O ring 9. The four-way valve 71 is operated so that air under pressure from inlet hose 57 is passed from the four-way valve through the corresponding pipe 74 or 75 to the inlet 82 or 82a of the desired tank.

This setting of the four-way valve will cause air to be exhausted from the other tank through the four-way valve and discharged to the atmosphere through the exhaust side 79 of said valve.

Assuming that dust is to be discharged from the right hand tank 1, as viewed in the drawings, the handle 17 thereof is depressed to raise the cone 11 as above described, the four-way valve handle 72 will be moved to a position to set the valve so that air under pressure from the inlet hose 56 will pass through the air filter 58, pipe 62, valve 63, T-coupling 65, four-way connection 67, pipe 70, inlet 78 of the four-way valve through the right side 77 thereof, pipe 75, T-connection 80a, pipe 81a, connection 82a to the upper portion of the right hand tank 1. At the same time air passes downwardly from the T-connection 80a through the pipe 83a to the vibrator 8411, operating the vibrator to vibrate the conical hopper bottom 19 of the right hand tank 1.

Air pressure is thus maintained in the upper portion of the right hand tank 1 on top of the rock dust therein, forcing the rock dust down through the conical bottom 19 of said tank through the pipe fitting 21 and hose 29 thereof to the outlet junction 31.

As shown in FIG. 5, the air and dust being discharged from the right hand tank 1 will throw the flipper valve 43 to the full line position shown in said figure, closing the outlet from the left hand tank 1 to the outlet junction 31.

The four-way valve 71, when set in the above indicated position, will cause air to be exhausted from the left hand tank 1 through the coupling 82, pipe 81, Teennection 8t) and pipe 74 to the left side 76 of the four-way valve and exhausted to the atmosphere through the lower side 79 of said valve.

At the same time that the air is being exhausted from this tank, the closure cone 11 thereof will drop by gravity so that rock dust may be charged into the left hand tank while dust is being discharged from the right hand tank.

The flipper valve 43 is an important part of the apparatus, as it always automatically seals the outlet from the tank being filled with rock dust. It will be obvious that this flipper valve is automatically operated by the pressure of air and dust being discharged through the outlet junction 31 from the other tank.

Once the flipper valve has been thrown to the closed iposition, for the tank being filled, it will be held in this position by the difference in pressure between that in the outlet junction and that in the tank being exhausted through the four-way valve, and will remain in this position until the four-Way valve is operated to reverse position.

This operation is repeated, discharging the dust from one tank while the other tank is being filled and then reversing the position of the four-way valve so as to discharge dust from the second tank while the first tank is being filled, the flipper valve 43 being automatically operated, as above described, by pressure from the outlet of the tank discharging dust to automatically close the outlet from the tank being filled with dust.

It will be obvious that regardless of the position of the four-way Valve or the position of the flipper valve, the cleanout jets 53 will operate continuously so long as there is air pressure in the system, so as to constantly maintain the bearing of the flipper valve free of dust and dirt.

In the foregoing description certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for descriptive purposes herein and are intended to be broadly construed.

Moreover, the embodiments of the improved construction illustrated and described herein are by Way of example, and the scope of the present invention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, the operation, and use of preferred embodiments thereof, and the advantageous new and useful results obtained thereby; the new and useful construction, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

ll. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, a four-way valve for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction and for simultaneously exhausting air from the other tank to the atmosphere, and a flipper valve in said outlet junction, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

2. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, an air-operated vibrator mounted near the outlet of each tank, a four- Way valve for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction and for simultaneously admitting air under pressure to the corresponding vibrator, and for simultaneously exhausting air from the other tank to the atmosphere, and a flipper valve in said outlet junc tion, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

3. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefore, an outlet for each tank, an outlet junction, means connecting the out lets of both tanks to said outlet junction, means for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve bting arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

4. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, means for selectively admitting air under pressure to either tank to discharge d-ust from the outlet thereof through said outlet junction and for simultaneously exhausting air from the other tank to the atmosphere, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

5. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, a four-way valve for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction and for simultaneously exhausting air from the other tank to the atmosphere, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

6. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefore, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, an air-operated vibrator mounted near the outlet of each tank, means for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, and for simultaneously admitting air under pressure to the corresponding vibrator, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

7. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a. charging opening and a closure therefor, an outlet from each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, an air-operated vibrator mounted near the outlet of each tank, means for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, and for simultaneously admitting air under pressure to the corresponding vibrator, and for simultaneously exhausting air from the other tank to the atmosphere, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

8. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet from each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, an air-operated vibrator mounted near the outlet of each tank, a four-way valve for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, and for simultaneously admitting air under pressure to the corresponding vibrator, and for simultaneously exhausting air from the other tank to the atmosphere, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction adjacent to said pivot pin, jet passage means communicating with said bore and directed toward said bearing portion of the flipper valve, and

means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

9. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, means for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, a pivot pin located through the outlet junction between said outlets from the tanks, a flipper valve in said outlet junction and having a bearing portion journalled upon said pivot pin, there being a bore in a wall of the outlet junction, jet passage means communicating with said bore and directed adjacent to said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

10. A rock duster comprising a pair of similar tanks for containing rock dust and the like, each tank having a charging opening and a closure therefor, an outlet for each tank, an outlet junction, means connecting the outlets of both tanks to said outlet junction, means for selectively admitting air under pressure to either tank to discharge dust from the outlet thereof through said outlet junction, a flipper valve in said outlet junction and having a bearing portion journalled therein, there being a bore in a wall of the outlet junction, jet passage means communicating with said bore and directed adjacent to said bearing portion of the flipper valve, and means for supplying air under pressure to said bore, said flipper valve being arranged to be operated by the pressure of the discharge from either tank to close the outlet from the other tank.

References Cited by the Examiner UNITED STATES PATENTS 1,566,536 12/ 1925 Hoving 302-53 2,108,416 2/ 1938 Smith 302-56 2,221,741 11/ 1940 Vogel-Jorgensen 302-53 2,819,679 1/1958 Wilson ZZZ-386.5 3,058,780 10/ 1962 Swanson 302-49 SAMUEL F. COLEMAN, Primary Examiner. ANDRES H. NIELSEN, Examiner. 

3. A ROCK DUSTER COMPRISING A PAIR OF SIMILAR TANKS FOR CONTAINING ROCK AND THE LIKE, EACH TANK HAVING A CHARING OPENING A CLOSURE THEREFORE, AN OUTLET FOR EACH TANK, AN OUTLET JUNCTION, MEANS CONNECTING THE OUTLETS OF BOTH TANKS TO SAID OUTLET JUNCTION, MEANS FOR SELECTIVELY ADMITTING AIR UNDER PRESSURE TO EITHER TANK TO DISCHARGE DUST FROM THE OUTLET THEREOF THROUGH SAID OIUTLET JUNCTION, A PIVOT PIN LOCATED THROUGH THE OUTLET JUNCTION BETWEEN SAID OUTLETS FROM THE TANKS, A FLIPPER VALVE IN SAID OUTLET JUNCTION AND HAVING A BEARING PORTION JOURNALLED 